Mica chimney.



No. 765,528. PATENTED JULY 19', 1904 J. 1). WARREN.

MIGA CHIMNEY.

APPLICATION FILED JAN. 8, 1904.

N0 MODEL.

UNITED STATES Patented July 19, 1904:.

PATENT OEEICE.

JOHN D. WARREN, OF NEW YORK, N. Y., ASSIGNOR OF ONE-HALF TO EUGENEMUNSELL & CO., OF NEW YORK, N. Y., A PARTNERSHIP.

MICA CHIMNEY.

SPECIFICATION forming part of Letters Patent No. 765,528, dated July 19,1904.

Application filed January 8, 1904.

To all whom it may concern.-

Be it known that I, JOHN D.WARREN, a citizen of the United States,residing at New York, in the county of New York and State of New York,have invented a new and useful Mica Chimney, of which the following is aspecification.

This invention relates to a lamp-chimney which is constructed to securea free circulation of air therein.

The especial object of this invention is to provide a strong, simple,and efficient construction which may be made of mica or similartransparent material.

To this end this invention consists of the chimney as an article ofmanufacture and of the combinations of parts therein, as hereinafterdescribed, and more particularly pointed out in the claims at the end ofthis specification.

In the accompanying drawings, Figure l isa side view, partly brokenaway, of a chimney constructed according to this invention. Fig.

i 2 is a perspective view of one end of a partly- ?completed chimney.Fig. 3 1s a slmilar view showing the ends of the joint-strips bent intoward each other to receive the end ring. FigI-A is a fragmentary viewshowing the base-"ring slipped onto the ends of the jointstrips. Fig. 5is a perspective view of one end of the completed chimney, and Fig. 6 isan enlarged detail view showing a joint-strip and part of afmica sectionat each side thereof.

In the use of a larger and more powerful incandescent gas-burner it isessential that a free circulation of air should be secured inside of thechimneys. This is due to the excessive heat. which is generated by thelarge Bunsen burners required for use in connection with the larger andmore closely-woven incandescent mantles.

In practice when it is attempted to use the ordinary lamp-chimney inconnection with these large incandescent gas-burners it has been foundthat the heat of the burner when confined within the lamp-chimney willbe sufficient to fuse the metal supports of the incandescent gas-mantlesand to overheat all parts of the burner. To overcome this ob- Serial No.188,234. (No model.)

jection, it is necessary to employ lamp-chimneys having draft-openingsnear their bottom. Heretofore in the use of the large incandescentgas-burners these ventilated chimneys have been made of glass, theventilating-openings being left through the sides of the chimney whenthe glass is blown or molded into shape.

Perforated bottom glass chimneys are comparatively expensive, and assuch chimneys are frequently broken the cost of chimneys is one of thelargest, if not the largest, item in the expense of maintaininglarge-sized incandescent gas-burners.

A lamp-chimney constructed according to this invention has been designedto overcome these objections by providing an open-bottom lamp-chimneyhaving a body portion of mica and which may be manufactured in a simple,inexpensive, and efficient manner.

A lamp-chimney constructed according to this invention, as hereinillustrated, comprises a body portion of transparent pieces of mica,which are connected by sheet-metal jointstrips. The joint-strips projectbeyond one end of the body portion of the chimney and are connectedlaterally to a base-ring or support. The base-ring is preferably ofsmaller diameter than the body portion of the chimney, so that asubstantially unobstructed annular opening is left between the base-ringand the body part.

Referring to the accompanying drawings for a detail description of achimney constructed according to this invention the body part of thechimney comprises the pieces 10 of transparent mica.

I have illustrated the body part of the chimare back to back, so thatthe edges of the adjacent mica sections are fastened together .N I Vwithout overlapping or unnecessary waste of mica. It is to beunderstood, however, that I do not claim in this application for patentany particular form of sheet-metal joint-strip for connecting the piecesof mica.

The body part of the chimney may be finished by the ordinary end ringsor bindings 12, which are fastened in place by the small eyelets 13. Thejoint-strips 11 extend beyond one end of the body part of the chimney,and the ends of these joint-strips are first bent in toward eachother,-as illustrated in Fig. 3. An end ring or base-section let is thenslipped onto the joint-strip. As shown in Fig. 4, the base-ring 14 isprovided with a flange or bentin section 15, and the ends of thejoint-strips extend into the annular space between the base-ring l landflange 15. The parts are secured together by pinching or bending backthe flange 15 to grip the ends of the jointstrips, as shown in Fig. 5 at16. By means of this construction a ventilated mica chimney is providedwhich consists of comparatively few .parts,'which are assembled andsecured together without the use of solder or other fusible material. Inthe use of the lam p-chimneys as thus constructed the substantiallyunobstructed annular space between the basering and body portion of thechimney will permit a free circulation of air up inside the chimney, andthe excessive heat of a Bunsen burner will not be confined within thelampchimney. In the use of this construction the air will rise upthrough the body partof the chimney in substantially an uninterruptedannular column, giving equal drafts upon all sides of the incandescentmantle of the burner, and I regard this as of advantage, as uniformeffects Will be produced on all parts of the mantle, whereas where thelamp-chimneys are provided with a series of ventilating-holes theseholes will tend to concentrate the aircurrents at different points onthe mantle.

I am aware that numerous changes may be made in manufacturing chimneysaccording to my present invention without departing from the scopethereof as expressed in the claims. I do not wish, therefore, to belimited to the construction I have herein shown and described; but

What I do claim, and desire to secure by Letters Patent of the UnitedStates, is

1. As a unitary article of manufacture, a mica chimney and a base-ringof smaller diameter than the chimney connected laterally thereto andleaving a substantially open annular space between the base-ring andbottom of the chimney.

2. As a unitary article of manufacture, a chimney comprising a number ofsections of mica connected to form a body part, a sheetmetal base-ringof smaller diameter than the body part, and laterally-extending metallicsupporting-arms permanently connecting the base-ring and body part ofthe chimney and leaving a substantially open annular space between thebottom of the body part and the base-ring.

3. As an article of manufacture, a chimney comprising pieces oftransparent material, joint-strips connecting said pieces to form thebody part of the chimney, said joint-strips extending beyond the end ofthe-body part and a base-ring fastened to the joint-strips.

4. As an article of manufacture, a chimney comprising transparent micapieces, jointstrips connecting the pieces to form the body part of thechimney, said joint-strips extending beyond the end of the body part ofthe chimney, and being bent in toward each other, and a base-ring ofsmaller diameter than the body part connected to the ends of thejointstrips, a substantially unobstructed annular space being leftbetween the base-ring and body part of the chimney.

5. As an article of manufacture, a chimney comprising transparent piecesof mica, jointstrips connecting the pieces of mica to form the body partof the chimney the ends of the joint-strips extending beyond the end ofthe body part of the chimney, and a sheet-metal base-ring having aturned-in flange bent into engagement with the ends of the joint-stripsto fasten the base-ring thereon.

6. As an article of manufacture, a chimney comprising transparent piecesof mica, sheetmetal jointstrips connecting the pieces of mica to formthe body part of the chimney, end rings connected by eyelets to thejointstrips, the joint-strips projecting from one end of the bodyportion of the chimney, and said joint-strips being bent in toward eachother, and a base-ring having a bent-in flange compressed intoengagement with the jointstrips to hold the base-ring in place, andforming a chimney having a substantially unobstructed annular spacebetween its body portion and base-ring.

In testimony whereof I have hereunto set my hand in the presence of twosubscribing witnesses.

JOHN D. WARREN.

WVitnesses:

EDWARD C. 001), E. G. HEALD.

